ABSTRACT:Leader Member Exchange theory believes that leaders from different relationships with different members ranging from high quality to low quality. High quality relationships exist with in-group members and are characterized by mutual trust, respect, and responsibility while as low quality exist with out-group members and are restricted to economic exchanges, formal job requirements. LMX has been in significant relationship with various job attitudes like employee satisfaction, involvement, engagement across different service sectors like health, hospitality. However, exploration of LMX in service sectors like insurance, banking and postal is rare in LMX literature. Therefore, the current study would study LMX in relation with perceived organizational support, Organizational Citizenship Behavior and service performance of employees across banking, insurance and postal service sectors of the State of Jammu and Kashmir. The Survey method with structured questionnaires and interviews are used as techniques of data collection. A sample size of 100 respondents representing middle management, frontline staff, lower level employees and customers were part of the study. Data was analyzed using data analysis tool SPSS. Techniques like descriptive statistics and multiple regression analysis were used to analyze and interpret data and results. The statistical coefficients revealed significant and positive relationship between LMX and POS; LMX and OCB; LMX and Service Performance; POS and Service Performance and OCB and Service Performance.